One of these special containers will typically be inlaid with runes of silver and stoppered by a brass plug bearing a seal of great dweomer set round with sigils, glyphs, and special symbols. 

When the user speaks a command, he or she can force any creature from another plane (daemon, demon, devil, elemental, etc.) into the container, provided the creature does not make its saving throw versus magic—after magic resistance, if any, is checked. 

Range is 6". 

Only 1 creature at a time can be so contained. 

Loosing the stopper frees the captured creature; and if the individual loosing the plug knows the command word, the creature can be forced to serve for 1 turn (or to perform a minor service which takes up to 1 hour of time). 

If freed without command knowledge, dice for the creature's reaction... 

Any attempt to force the same creature into the flask a second time allows it +2 on its saving throw and makes it VERY angry and totally hostile. 

A discovered bottle can contain: